How to Treat Swimming Pool Water to Green

It’s a no-brainer when you pull up the pool cover and notice that the water is turning green and cloudy. This means that your pool is temporarily colonized by algae and you will need to clean and treat it thoroughly before swimming. Read on to learn how to get rid of this scary green water.

Table of Contents

Get ready to handle the pool

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Test the water in the pool. Use a chemical test kit to check chlorine and pH levels and determine the extent of the problem. Algae can grow and turn pool water green when chlorine levels drop below 1 ppm. “Shocking” the water with chemicals is a necessary measure to kill the algae and bring the pool back to normal chlorine levels.

Proper pool maintenance, ensuring that the filters are working and that chlorine and pH levels in the pool remain stable, this step can prevent algae growth in the first place.
Algae will constantly multiply, so if the pool is left untreated for just a few days, the water in the pool will turn green.

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Chemical balance in the pool. Before proceeding with swimming pool treatment, you should balance the pH level around 7.8 by adding an acid or base. This is the ideal level to have in your pool and is only really necessary when you are doing algae removal. Here’s how to balance the pH:

Turn on the pump so the chemicals can circulate throughout the pool.
Adjusting the pH again, you can increase the pH with sodium carbonate or decrease the pH with sodium bisulfate.

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Make sure the filter is still working properly. Clear leaves, sticks, and debris that could clog the filter. If necessary, before adding chemicals to your pool to kill algae, you should backwash the filter and make sure it’s still in good working order. Set the filter to run 24 hours a day, during the cleaning process, the filter system will remove all algae.

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Scrub the walls and bottom of the pool. Be sure to use a pool-appropriate brush to scrub the tank clean before putting chemicals in the water. Algae often cling to the surface of the pool, but this scrubbing step will remove them. Scrubbing also helps break down the algae’s topology, allowing the chemical to work faster.

Pay close attention to scrubbing areas with signs of algae buildup. You should try to break the topology of the algae so that the pool is completely clean.
You should use a nylon brush for vinyl pools. Metal brushes can cause damage to vinyl slurry, but are safe to use on plaster.

Shock the pool

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Treat the pool with pool shock. Shock the pool with a large dose of chlorine to kill algae and disinfect the pool. You should choose a strong shock product with a shocking chlorine content of 70%, which is enough to kill stubborn algae and bacteria. Follow the instructions on the product packaging to ensure that you are using the correct dose for the water in your tank.

If the amount of algae in the pool is quite large, you may need to treat it more often to prevent the algae from continuing to grow.
Shocking the pool will make the water more cloudy and dirty, but the water will clear again when it flows through the filter.

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Treat the pool with an algaecide when the chlorine concentration in the water is below 5.0. Allow the algaecide to work in the pool for at least 24 hours.

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Clean the filter regularly to remove dead algae to avoid pressure build-up in the filter. When dead, the algae will settle to the bottom of the lake or float in the water and lose its inherent green color.

Complete the work

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Suction the algae left in the pool. Use a brush to clean the bottom and sides of the pool walls again, then suck up all the algae. If there are too many dead algae and it is difficult for you to suck them up, you can add a coagulant to help the algae stick together and suck up the dead algae will become easier. ^{[1] X Research Source}

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Run the filtration system until the algae is completely gone. After the treatment process, the pool water will gradually clear again. If algae shows signs of reappearance, repeat the shock and treatment process again until the algae is completely eliminated.

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Double check chemical levels with a pool test kit. All chemical concentrations should be within the normal range.

Advice

Use a pool net every day to keep out leaves and other floating objects on the surface of the pool. It will be easier for you to clean up the trash before it settles to the bottom of the lake.
Wear old clothes when using pool chemicals. Chlorine splashed or dripped onto clothing can discolor the garment.
You can take a water sample and take it to your local pool store on a fixed monthly basis and get the water sample analysis data back from the computer. With this method, you can identify water problems in your pool early.
Chlorine levels should be maintained between 1.0 and 3.0 ppm to prevent algae from re-growing in the pool.

Warning

Do not add any chemicals to the pool if you do not know what to do. Adding the wrong chemical will cause more problems.
Use extreme caution when dealing with chlorine. Chlorine can cause sore throat symptoms, cough, or irritation to the eyes, skin, and respiratory system.
Use caution when mixing chemicals with water. Always mix chemicals in water, not the other way around.
Never mix chemicals together.

Things you need

Chemical test kit
Pool scrub brush
Chlorine to apply shock measures
Algae Killer
Vacuum cleaner swimming pool
Pool net

Steps